Red sulfur dye and process of making same.



' T0 all-whom it may concern.-.

following is 'a' specification: p

the manufacture PAUL FRiEDLAENDER, or v ENNA; USTR MHUNGARY,.AsslcNoa Toj THE FIRM or KALLE' EAND COMPANY:AKTIENGESELLSQHAFT, or

B'IEBRICH; GERMANY.

RED SULFUR DYEAND OCESS oF M KimesAME.

Specification oiLetters iatent.

A uau a filed November 16.1905. see-i1 No. 257,728. "(Specimens-l Be itknown-that 1, PAUL FRIEDLAENDEIg doctor of philosophy fa subject of theEmperor of Austria Hungary residingat Vienna,

Austria Hungary, have invented certain new and useful Improvements in aRed Sulfur Die and Process of-Making Same, of which t e.

This invention relates to "of a new redcoloring-matter;

,I havefound that the heml'cal compbunds described in" my'applica'tionfor Letters Pat- I ent, Serial No; 287,727,1 bearing thesame date, the. constitution ofjwhich is defined by in which formula Xstandsfor a hydrogen latom (H) or fora carboxylicgroup (COOH) "havingthe property to be easily transformed the following general formula Q aI cfin l by the action of oxidizing agents into a red sulfurcontainingcoloring-111atter, to which most probably the constitution correspondmgto 'the, :following formula may be ascr bed:

' Theicompound i I call thio indo'xyl carboxylic acid. The compound "cCOH I call i thio -indoxyli The new coloring-matter is in the dry statea red powder'which sublimesvon heating without decomposition, formingbrilliant bronze-coloredineedles.' The new coloring-- matter dissolveswith great difficultyin the usual solvents; The solution in chloroformis a fine red with a s lendid yell'ow'fluorescehce; On treating thecoloring-maittefWith solution is obtained, from which thecoloringmatter-can be separated by oxidationviz.,

r a'tenteoi May 1,1906,

reducing agents an. almost colorless or yellow the access of a1r.and itsapplication to dyeing is based on this'property. Red'dye1ngs of"excellent fastness are-obtained both on animal and vegetable fibers.

f In that llowing I give a 881168 01 examples in which various modes-ofthe productionof the neW-coloring-matte'r by oxidizing thioindoxylor:thio-indoxyl-carboxylic acid are described.

Examplel; ia ikilbg ramsbf thioeindoxyl carboxyhc acid are dissolved inabout eighty The isolation of the coloring- .kilograms caustic-sodalyeof 40 Baum. This solution is then mixed with a solution of potassiumferricyanid as long as a red precipitate forms.

' matter isefiected by filtering, washing, and

obtaining iteitheras a paste or as'a red powder after drying. v

, Example '2: A current of air is passed through a Weak alkalinesolution or through an aqueous suspension of thio-indoxyl-carboxyhc'aciduntil the coloring-matter ceases to be formed in a t'estportion byfurther treatment i 'withair. The isolation of the coloring-matas by theprocess given in Example 1.

I i Exam le 3; 19.4 kilogramsof thio-indoXylvcarboxy 1c acid aredissolved water by the 1 addition of one hundred kilograms of causticsoda of 40 Baum.-' A solution of thirty- .ter can be eifected asabove'described. .-B.y

this method not as good' results are obtained seven kilograms of ferricchlorid (Fe Cl is then added. The mixture is heated, and

while it is being stirred hydrochloric acid is slowly added until themass is decidedly acid. Carbon dioxid is evolved simultaneously with theseparation-of'the red coloring-mat The filtrate containsneither.thi9-.indoxyl- I carboxylic acid nor thio-indoxyl.

' ter. It is filtered While hot and Well washed.

Exam le 4: 19.4 kilograms of thio-indoXylcarboxy ic acid are dissolvedin-Water by the addition of twenty-four kilograms of caustic-- sodalyeof 40 Baum. I A solution ofpotassium bichromate 'containingabout 9.3kilogramslof K Cr O is then added. The mixture is heated, and while itis being stirred an excess-.of hydrochloric acid is slowly added. Carbondioxid is evolved with simultaneous formation of the'redcoloring-matter, which further treatment with air. The

the same as hereinbefore described. In lieu of'th e isolatedthio-indoxyl-carboxylic acid a corresponding quantity of the reactionprodnot obtained 1n its manufacture may be used. Example 5: Seventy-fivekilograms of a paste containing twenty per cent. ofthio-indoxyl aredissolved in two hundred liters of water by the addition of twelvekilograms of caustic-soda lye of Baum. To the solution of sodium'.thio-indoxyl thus obtained thirty six kilograms of can stic-soda lye of40 Baum are added. A solution of potassium ferricyanid is run into thesolution under good agitation at ordinary temperature so long as a redprecipitate is formed. The precipitate is filtered and Washed, and thecoloring-matter is used in the form of, a paste or is dried. u

Example 6: Througha cold or moderatelyheated solution of thio-indoxyl'or of thio-indoxyl sodium, as prepared in Example 1, a current of air ispassed until no more precipitate is formed in a filtered test portion byrecipitate is then filtered and washed a litt e, and the coloring-matteris used as paste or is dried. Example 7: To a solution of thio-indoxylsodium prepared as explained in Example 5 a solution containing fortykilograms of ferric chlorid is added. The solution is then heated, anexcess of mineral acid is added, and the mass is then boiled for a shorttime. The separated coloring-matter is filtered and well washed. Noindoxyl can now be detected in the filtrate.

Example 8: To a solution of thio-indoxyl sodium prepared as explained inExample 5 is addeda solution of potassium bichromate In the foregoingexamples the mode of preparation of the new coloring-matter is describedin a general way; but I do not bind myself to the proportions stated norto the mode of operation nor to the oxidizing agents mentioned.

Now what 'I claim is' 1. As a new process the manufacture of a redsulfur containing coloring-matter byacttion:

in which formula X stands for a hydrogen atom (H) or for a carb oxylicgroup (CODE).

ing with oxidizing agents on the thio-indoxyl compounds having thefollowing constitu 2. As a new product the sulfur-containingcoloring-matter obtained by oxidizing thioindoxyl compounds and havingvery probably the following constitution:

co 2 co y w 1 l which is in the dry state a red 'powder difficultlysoluble in the usual solvents, which sublimes on heating without[decomposition formingv brilliant bronze-colored needles and gives ontreatment with reducing agents a yellow solution, from which thecoloringmatter is reprecipitated by the access of air, and whichproduces on the textile fibers red shades of excellent fastness.

In testimonylwhereof I have signed my name to this specification in thepresence of two subscribing witnesses.

PAUL FRIEDLAENDER.

Witnesses:

IGNAs ROSENBERG, JEAN GRUND.

